1. Field Of The Invention
The present invention relates to user-programmable interconnect architectures. More particularly, the present invention relates to user-programmable interconnect architectures which do not employ active devices.
2. The Prior Art
Recent activity in integrated circuit and other microcircuit applications has focussed on user-programmable circuits which employ user-programmable interconnect architectures. Such architectures have become useful as circuit designers seek circuit design solutions which provide them with faster turn-around times for circuits under development.
There are numerous examples of user-programmable interconnect architectures known in the prior art. These prior art architectures utilize a mixture of active switching components, such as transistors, and passive components, such as fuse elements and antifuse elements. One example of a user-programmable interconnect architecture which relies completely on active transistor switching devices as both interconnect elements and the means to program the interconnect elements is disclosed in U.S. Pat. No. 4,870,302 to Freeman. An example of a user-programmable interconnect architecture which employs antifuse devices as the interconnect elements and also employs active semiconductor components to program the interconnect elements is disclosed in U.S. Pat. No. 4,758,745 to El Gamal et al.
User-programmable interconnect architectures have been used to provide field programmable logic arrays (FPLAs), field programmable gate arrays (FPGAs), as well as to provide memory redundancy and other user configurable circuit functions. The number and variety of applications for user-programmable interconnect architectures for interconnecting semiconductor circuits on integrated circuits is rapidly growing.
Applications for user-programmable interconnect architecture also include interconnection matrices, such as cross-point switches, which essentially comprise a large matrix of orthogonally disposed conductor segments which may be programmably interconnected by a user to form a customized interconnect pattern. Such structures have an increasing number of different uses.
In certain applications, it is sometimes advantageous to fabricate the user-programmable interconnect architecture on conductive substrates which have been covered by a layer of insulating material or on substrates fabricated from insulating materials. Fabrication of integrated active transistor switching devices capable of switching high voltages and high currents for use in programming the interconnect elements is more difficult when such substrates are employed. The difficulty to form active high-voltage, high-current transistor switching devices for use in programming the interconnections has heretofore presented a significant problem in the design of large-scale, dense interconnection matrices employing non-semiconductor substrates.
It is an object of the present invention to provide a user-programmable interconnect architecture which does not employ or require active semiconductor devices integrated with the interconnect architecture for any purpose.
It is a further object of the present invention to provide a user-programmable interconnect architecture which may be fabricated on a substrate which is formed from a conductive or non-conductive material.
Yet another object of the present invention is to provide an integrated, user-programmable interconnect architecture which may be completely programmed by the application of voltages and currents to externally-accessible conductor nodes.
These, and other objects of the present invention will become apparent to those of ordinary skill in the art from an examination of the following specification and accompanying drawing figures.